CA27.29: a valuable marker for breast cancer management. A confirmatory multicentric study on 603 cases

Recently, a fully automated method has become commercially available to mea sure the MUC-1-associated antigen CA27.29. The present investigation was pe rformed in order to compare CA27.29 and CA15.3 in a wide series of patients affected with breast cancer. Overall, 603 cases with breast cancer and 194 healthy controls were investigated. Patients were enrolled in 4 institutio ns, while assays were performed in one laboratory. CA27.29 was measured by the ACS:180 BR assay (Bayer Diagnostics) and CA15.3 by the AxSYM (Abbott La boratories). An excellent correlation was found between the results obtaine d by the two methods. The two markers showed comparable results in healthy controls, with higher levels in post-menopausal than in pre-menopausal subj ects. The markers were significantly higher in primary breast cancer than i n controls. The areas under the receiver operating characteristics (ROC) cu rves of the two tests were comparable, but CA27.29 showed better sensitivit y in cases with low antigen concentrations (below the cut-off point). Accor dingly, when comparing each test in different stage categories, significanc e levels of the differences were higher for CA27.29 than for CA15.3 for all T categories versus healthy controls, for pT1 versus pT2, for all N catego ries versus healthy controls and for node-negative versus N1-3 patients. Fr om the results of the present study, that has been performed on samples tak en at diagnosis and prior to any treatment from the widest series of patien ts with primary breast cancer reported so far, we can draw the following co nclusions: CA27.29 provides comparable results to CA15.3: CA27.29 seems mor e sensitive than CA15.3 to limited variations of tumour extension; however, it cannot help clinicians in distinguishing stage I patients from stage II patients. However, from the point of view of clinical decision making, CA2 7.29 provides comparable results to CA15.3. CA27.29 is therefore suitable f or routine use in the management of patients with breast cancer. (C) 2001 E lsevier Science Ltd. All rights reserved.